1. Field of the Invention
The present invention is suitable for application to cylinder liners and auxiliary combustion chambers in internal combustion engines, to crucibles and to other hollow structures that require heat insulation, heat retention, heat resistance and corrosion resistance.
2. Description of the Related Art
It is known that metallic tubular members such as pipes and rings can be provided with heat insulating, heat resisting and corrosion resisting properties by forming a ceramic layer on the inner surfaces of the structures. In order to attain this object, composites are used that have a sintered ceramic joined with metallic tubular members by known techniques such as shrink fitting, expansion fitting, press fitting and bonding with an adhesive.
These techniques however have their own problems. If a low stress is applied in joining by shrink fitting or expansion fitting, the thermal expansion mismatch between metal and ceramic may cause loosening of the mating surfaces depending upon the temperature at which the composite is used. If, on the other hand, an excessively large stress is applied, the ceramic may fail. In addition to these problems, joining by press fitting or bonding with an adhesive reduces process efficiency because the inside and outside diameters of the members to be joined must be closely controlled.
An object of the present invention is to provide a heat-insulating metal-ceramic structure that can be produced at high efficiency and which can be used over a broad range of temperatures without causing the loosening of one mating surface from the other or failure of the ceramic part.